Chip breaking device



Feb. 23, 1954 A. HULLER 2,669,889

CHIP BREAKING DEVICE Filed April 1, 1953 2 Sheets-Sheet 1 26 "Ill? INVE/WDK AooL HU'LLER Feb. 23, 1954 A, HULLER 2,669,889

CHIP BREAKING DEVICE Filed April 1, 1953 2 Sheets-Sheet 2 ADoLF HULLER BY W3? Patented Feb. 23, 1954 UNITED STATES PATENT OFFICE 2,669,889 CHIP BREAKING DEVICE Adolf Hiiller, Ludwigsburg, Germany Application April 1, 1953, Serial N 0.. 346,091

Claims.

It is an object of the present invention to provide a chip breaking device of simple and durable design, which may readily be attached to a drill press or a drill jig.

It is a further object of the invention to provide a chip breaking device which effectively cuts long chips into small pieces.

Other objects of the present invention will become apparent from the following description when considered in connection with the accompanying drawing, in which:

Fig. 1 is a partial side view of a drill press partly in section with the chip breaking device according to the invention fastened to a holding attachment,

Fig. 2 is a longitudinal sectional view of the chip breaking device,

Fig. 3 is a transverse section on line 33 of Fig. 2,

Fig. 4 is a top view of the chip deflector of the chip breaking device according to Fig. 2,

Fig. 5 is a longitudinal sectional view of the chip breaking device in operation,

Fig. 6 is a side view of another attachment for holding the chip breaking device according to the invention.

A preferred embodiment of my invention sleeve member fleeting element rotatably arranged in said sleeve member, a bottom wall provided on said deflect ing element, said wall having a central opening of the shape of the cross-section of a twist drill, and limiting means for limiting the axial motion of said rotatably arranged deflecting element in both directions.

In a partly shown machine frame A of a drill press having a head portion I ii, a table I 2 and a back portion II, a spindle I3 is rotatably but non-slidably arranged in a sleeve IN, the latter being axially slidably provided in the machine frame in known manner. The driving means for driving spindle I3 are not shown in the drawing, since they form no part of the invention. In spindle l3 a drill chuck 26 of known construction i'sznon-rotatably secured, in which a twist drill I110! conventional design is clamped in place.

Attached to sleeve I BI is a holding attachment B which will now be described.

The holding attachment B comprises a holding member 15 having a cylindrical hole I5l parallel to the axis of spindle I3. A slotted clamping portion I52 of said holding member fits over sleeve It". By means of a clamping device I6 with an operating handle tion I52 and thus the entire holding attachment B is fastened to sleeve I3I in known manner. The holding member I5 receives in its hole 15! an intermediate member I? which is closed at its upper end by means of a top wall Ill and provided at its lower end with a thread I12, said intermediate member I? being adjustably at tached to holding member I5 by means of a clamping device I8. The latter forces with its operating handle I the clamping portions I53 of holding member I5 together with the result that the intermediate member I! is secured in place with respect to the holding member I5. Disposed in hole ill of the intermediate member I? is a piston member I9 having a cylindrical portion l9! slidably fitting into said hole Ill and a cylindrical portion I92 of smaller diameter extending through the lower opening of the intermediate member I I and also through a cap 20 screwed on the threaded end portion of intermediate member II. Inside the intermediate member I! two helical springs 2i and 22 are arranged, the first bearing against the circular face L93 of piston member I9 and the top wall I?! of the intermediate member I7, and the second abutting the annular surface I94 of piston member i9 and the inside surface of cap 29.

Fastened to the downwardly extending end of portion I92 by means of a fastening pin 26 is a bracket 23 which carries a chip breaking device C resting in operating position with its lower surface on the upper surface of work 25 clamped to the table I2 in known manner not shown in the drawing, e. g. by magnetic or mechanical means. The chip breaking device C is fastened to bracket 23 by a screw 2'! extending through a hole of said device and screwed into a threaded hole of said bracket. Cooling liquid may be passed through a line 28 to the lower part of the chip breaking device C from where it may be supplied through a recess to drill M. when the latter is in operating position. Another position of the cooling liquid line is shown in dotdash lines above the chip breaking device at 29.

The chip breaking device C (vide Figs. 2. to 5) comprises a bushing 39 which rests with its flan e so! on the upper surface of the;

I (H, said clamping porespecially aforementioned bracket 23 and extends with its lower portion through a hole of that bracket. At the lower portion of bushing 30 projecting downwardly from bracket 23 three holes 3| are provided having the shape of a truncated cone so that the cross-section of the holes increases steadily in radial direction starting from the innermost portion of the hole, the latter forming cutting edges 3| I whose function will be described further down. At the lower end portion of bushing 30 a recess 302 is provided for receiving the pipe end of pipe 28 through which cooling liquid may be supplied to the twist drill M. The bushing 30 is fitted with an upper internal shoulder 303 and a lower internal shoulder 304 of tapered shape. A guiding sleeve 32 having a conical opening and a flange 32| fitting on the shoulder 303 is pressed into the bushing 30, so as to be rigidly attached to the latter. Below the guiding sleeve 32 a ch p deflector 33 is rotatably arranged in bushing 30, the conical bottom wall 333 of the chip deflector 33 resting on the tapered shoulder 304 of bushing 30 as shown in Fig. 2, for instance when the chip breaking device C is not in operation. The lower shoulder 304 is provided at such a place that the lower outside portion 33| of the ch p deflector 33 extends partly into the holes 3|. The axial play of the chip deflector 33 between shoulder 304 and the lower face 322 of guiding sleeve 32 is such that the deflector 33 still extends with the aforementioned portion 33| somewhat into holes 3| when the chip deflector is in its uppermost position, i. e., when face 332 of the chip deflector abuts face 322 of guid ng sleeve 32. In the conical bottom wall 333 of the chip deflector 33 an opening 334 is provided having the shape of the cross-section of twist drill l4, but being somewhat larger than the latter in order to admit cooling liquid flowing downward from the upper portion of the ch p breaking device, when the cooling liquid line is arranged in the position shown in dot-dash lines in Fig. l.

The operation of the chip breaking device will now be expla ned especially in connection with Figs. 1 and 5. When spindle |3 is in its upper position, spring 2| being stronger than spring 22 forces piston member |9 into its lowermost position with respect to the intermediate member |l. When sp ndle I3 is moved downward a certain length, the chip breaking device C will abut the upper surface of work 25, whereupon the downward motion of bracket 23 together with the chip breaking device C attached to it will come to an end. When spindle I3 is moved still further in downward direction, spring 2| w ll be compressed by the intermediate member I! moving downward together with holding member l5 secured to sleeve I3 I. Now the drill M will enter the chip breaking device C through the internal hole of guiding member 32 and pass through opening 334 of chip deflector 33, When the t p I43 of drill I4 is fed beyond the lower face of bushing 30 the drilling operation will start. The revolving drill M will also rotate the chip deflector 33 inasmuch as the bottom wall 333 extends into the flutes |4| of twist drill l4 and is thus forced to revolve. The remaining parts of the chip breaking device will remain stationary, since bushing 30 is secured to bracket 23 which also remains stationary during the drilling operation.

When drill l4 rotates and is fed into work 25 in known manner, the drill will cut off long curled chips 34 which slide upwards in the flutes |4| of drill l4. When the curled chips 34 reach thelower surface of bottom wall 333 of chip defleqtolj 33, they will raise the chip deflector 33 into its uppermost position and be deflected towards holes 3| through which they try to escape. When the chips have progressed a certain small length through holes 3|, the lands |42 of the rotating drill M will, when passing the cutting edges 3 of holes 3|, cut off short pieces 34| extending into the holes 3 said pieces depending in their lengths on the speed of drill l4. r

By the arrangement of portion 33| extending somewhat into the holes 3| it is insured that chips 34 reach the holes 3| readily without any obstruction.

In Fig. 6 another mode of holding the chip breaking device is shown. On a table 44 of a machine frame a fixture 40 is fastened by means of screws 4|, the fixture comprising a lower plate 40| on which a work piece 43 rests and an upper bracket 402 extending over work 43. Through an adjustable screw 42 the work is secured in place. The chip breaking device C is provided in a hole of the bracket 402 of fixture 40, where it is rigidly held in place by known means, e. g., a screw screwed into a threaded hole of bracket 402.

Without further analysis, the foregoing will so fully reveal the gist of my invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the mean ng and range of equivalence of the following claims. What I claim as new and desire to secure by Letters Patent is:

1. Chip breaking device for breaking long chips produced when drilling work by means of a twist drill into small pieces comprising a sleeve member through which the drill is adapted to be directed, said sleeve having at least one hole near its lower end portion forming an inner cutting edge, holding means adapted to hold said sleeve member stationary during the drilling operation, a deflecting element rotatably arranged in said sleeve member, a bottom wall provided on said deflecting element, said wall having a central opening of such shape that at least one driving portion extends into a flute of a twist drill passing through said opening, limiting means for limiting the axial motion of said rotatably arranged deflecting element in both directions.

2. Chip breaking device for breaking long chips produced when drilling work by means of a twist drill into small pieces comprising a sleeve member through which the drill is adapted to be directed, said sleeve having three holes disposed by near its lower end portion forming an inner cutting edge, to hold said sleeve member stationary during the drilling operation, a deflecting element rotatably arranged in said sleeve member, a bottom wall provided on said deflecting element,

said wall having a central opening of the shape of the cross-section of a twist drill, limiting limiting the axial motion of said rodeflecting element in both dimeans for tatably arranged rections.

3. Chip breaking chips produced when a twist drill comprising a sleeve member through which the drill is adapted to be directed, sleeve being fitted with at least one hole near its lpwer end portion forming an innercutting edge,

device for breaking long holding means adapted I drilling work by means of said sleeve having an internal shoulder, a holding means adapted to hold said sleeve member stationary during the drilling operation, a defleeting element rotatably arranged in said sleeve member, a bottom wall provided on said deflecting element, said wall having a central opening of the shape of the cross-section of a twist drill, said shoulder limiting the downward axial moelement, limiting means for limiting the axial motion of the deflecting element in upward direction.

4. Chip breaking device for breaking long chips produced when drilling work by means of a twist drill comprising a sleeve member through which the drill is adapted to be directed, said sleeve being fitted with at least one hole near its lower end portion forming an inner cutting edge, said sleeve having an internal tapered shoulder, a holding means adapted to hold said sleeve member stationary during the drilling operation, a. deflecting element rotatably arranged in said sleeve member, a conical bottom wall provided on said deflecting element, said wall having a central opening of the shape of the cross-section of a twist drill, said shoulder limiting the downward axial motion of said deflecting element, limiting means for limiting the axial motion of the deflecting element in upward direction.

ing element, said wall 5. Chip breaking device for breaking long chips produced when drilling work by means of a twist drill comprising a sleeve member through which the drill is adapted to be directed, said sleeve being fitted with at least one hole near its lower end portion forming an inner cutting edge, said sleeve having an internai shoulder, a holding means adapted to hold sleeve member stationary during the drilling operation, a defleeting element rotatably arranged in said sleeve member, a bottom wall provided on said deflecthaving a central opening of the shape of the cross-section of a twist drill, said shoulder limiting the downward axial motion of said deflecting element, a guiding n1ember fitting into the inside of the sleeve member secured to the upper portion of same, said guiding member having a hole for receiving the drill and serving as upper limiting means for limiting the axial motion of the deflecting member.

ADOLF HULLER.

References Cited in the file of this patent UNITED STATES PATENTS 

